[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:06.89,0:00:11.22,Default,,0000,0000,0000,,Deep beneath the geysers and hot springs \Nof Yellowstone Caldera
Dialogue: 0,0:00:11.22,0:00:16.18,Default,,0000,0000,0000,,lies a magma chamber produced by a \Nhot spot in the earth’s mantle.
Dialogue: 0,0:00:16.18,0:00:19.08,Default,,0000,0000,0000,,As the magma moves towards \Nthe earth’s surface,
Dialogue: 0,0:00:19.08,0:00:23.34,Default,,0000,0000,0000,,it crystallizes to form young, \Nhot igneous rocks.
Dialogue: 0,0:00:23.34,0:00:27.39,Default,,0000,0000,0000,,The heat from these rocks drives \Ngroundwater towards the surface.
Dialogue: 0,0:00:27.39,0:00:32.88,Default,,0000,0000,0000,,As the water cools, ions precipitate out \Nas mineral crystals,
Dialogue: 0,0:00:32.88,0:00:36.88,Default,,0000,0000,0000,,including quartz crystals from silicon \Nand oxygen,
Dialogue: 0,0:00:36.88,0:00:41.89,Default,,0000,0000,0000,,feldspar from potassium, aluminum, \Nsilicon, and oxygen,
Dialogue: 0,0:00:41.89,0:00:45.13,Default,,0000,0000,0000,,galena from lead and sulfur.
Dialogue: 0,0:00:45.13,0:00:47.74,Default,,0000,0000,0000,,Many of these crystals have signature \Nshapes—
Dialogue: 0,0:00:47.74,0:00:52.86,Default,,0000,0000,0000,,take this cascade of pointed quartz, \Nor this pile of galena cubes.
Dialogue: 0,0:00:52.86,0:00:57.32,Default,,0000,0000,0000,,But what causes them to grow into these\Nshapes again and again?
Dialogue: 0,0:00:57.32,0:01:00.01,Default,,0000,0000,0000,,Part of the answer lies in their atoms.
Dialogue: 0,0:01:00.01,0:01:04.93,Default,,0000,0000,0000,,Every crystal’s atoms are arranged \Nin a highly organized, repeating pattern.
Dialogue: 0,0:01:04.93,0:01:08.51,Default,,0000,0000,0000,,This pattern is the defining \Nfeature of a crystal,
Dialogue: 0,0:01:08.51,0:01:10.52,Default,,0000,0000,0000,,and isn’t restricted to minerals—
Dialogue: 0,0:01:10.52,0:01:15.76,Default,,0000,0000,0000,,sand, ice, sugar, chocolate, ceramics, \Nmetals, DNA,
Dialogue: 0,0:01:15.76,0:01:19.68,Default,,0000,0000,0000,,and even some liquids have \Ncrystalline structures.
Dialogue: 0,0:01:19.68,0:01:22.46,Default,,0000,0000,0000,,Each crystalline material’s atomic \Narrangement
Dialogue: 0,0:01:22.46,0:01:25.70,Default,,0000,0000,0000,,falls into one of six different families:
Dialogue: 0,0:01:25.70,0:01:32.32,Default,,0000,0000,0000,,cubic, tetragonal, orthorhombic, \Nmonoclinic, triclinic, and hexagonal.
Dialogue: 0,0:01:32.32,0:01:34.36,Default,,0000,0000,0000,,Given the appropriate conditions,
Dialogue: 0,0:01:34.36,0:01:37.01,Default,,0000,0000,0000,,crystals will grow into geometric shapes
Dialogue: 0,0:01:37.01,0:01:39.70,Default,,0000,0000,0000,,that reflect the arrangement \Nof their atoms.
Dialogue: 0,0:01:39.70,0:01:44.58,Default,,0000,0000,0000,,Take galena, which has a cubic structure \Ncomposed of lead and sulfur atoms.
Dialogue: 0,0:01:44.58,0:01:46.62,Default,,0000,0000,0000,,The relatively large lead atoms
Dialogue: 0,0:01:46.62,0:01:50.93,Default,,0000,0000,0000,,are arranged in a three-dimensional \Ngrid 90 degrees from one another,
Dialogue: 0,0:01:50.93,0:01:55.66,Default,,0000,0000,0000,,while the relatively small sulfur atoms \Nfit neatly between them.
Dialogue: 0,0:01:55.66,0:02:00.17,Default,,0000,0000,0000,,As the crystal grows, locations like these\Nattract sulfur atoms,
Dialogue: 0,0:02:00.17,0:02:03.66,Default,,0000,0000,0000,,while lead will tend to \Nbond to these places.
Dialogue: 0,0:02:03.66,0:02:07.10,Default,,0000,0000,0000,,Eventually, they will complete the grid \Nof bonded atoms.
Dialogue: 0,0:02:07.10,0:02:11.24,Default,,0000,0000,0000,,This means the 90 degree grid pattern \Nof galena’s crystalline structure
Dialogue: 0,0:02:11.24,0:02:14.59,Default,,0000,0000,0000,,is reflected in the visible \Nshape of the crystal.
Dialogue: 0,0:02:14.59,0:02:17.97,Default,,0000,0000,0000,,Quartz, meanwhile, has a hexagonal \Ncrystalline structure.
Dialogue: 0,0:02:17.97,0:02:22.10,Default,,0000,0000,0000,,This means that on one plane its atoms \Nare arranged in hexagons.
Dialogue: 0,0:02:22.10,0:02:27.56,Default,,0000,0000,0000,,In three dimensions, these hexagons are \Ncomposed of many interlocking pyramids
Dialogue: 0,0:02:27.56,0:02:31.79,Default,,0000,0000,0000,,made up of one silicon atom \Nand four oxygen atoms.
Dialogue: 0,0:02:31.79,0:02:34.17,Default,,0000,0000,0000,,So the signature shape of a quartz \Ncrystal
Dialogue: 0,0:02:34.17,0:02:39.57,Default,,0000,0000,0000,,is a six-sided column with pointed tips.
Dialogue: 0,0:02:39.57,0:02:41.69,Default,,0000,0000,0000,,Depending on environmental conditions,
Dialogue: 0,0:02:41.69,0:02:46.11,Default,,0000,0000,0000,,most crystals have the potential to form\Nmultiple geometric shapes.
Dialogue: 0,0:02:46.11,0:02:50.04,Default,,0000,0000,0000,,For example, diamonds, which form deep\Nin the earth’s mantle,
Dialogue: 0,0:02:50.04,0:02:56.26,Default,,0000,0000,0000,,have a cubic crystalline structure and can\Ngrow into either cubes or octahedrons.
Dialogue: 0,0:02:56.26,0:02:58.86,Default,,0000,0000,0000,,Which shape a particular \Ndiamond grows into
Dialogue: 0,0:02:58.86,0:03:01.15,Default,,0000,0000,0000,,depends on the conditions where it grows,
Dialogue: 0,0:03:01.15,0:03:05.45,Default,,0000,0000,0000,,including pressure, temperature, \Nand chemical environment.
Dialogue: 0,0:03:05.45,0:03:09.13,Default,,0000,0000,0000,,While we can’t directly observe growth \Nconditions in the mantle,
Dialogue: 0,0:03:09.13,0:03:11.87,Default,,0000,0000,0000,,laboratory experiments have shown some\Nevidence
Dialogue: 0,0:03:11.87,0:03:15.84,Default,,0000,0000,0000,,that diamonds tend to grow into cubes at \Nlower temperatures
Dialogue: 0,0:03:15.84,0:03:19.03,Default,,0000,0000,0000,,and octahedrons at higher temperatures.
Dialogue: 0,0:03:19.03,0:03:23.50,Default,,0000,0000,0000,,Trace amounts of water, silicon, \Ngermanium, or magnesium
Dialogue: 0,0:03:23.50,0:03:26.65,Default,,0000,0000,0000,,might also influence a diamond’s shape.
Dialogue: 0,0:03:26.65,0:03:31.26,Default,,0000,0000,0000,,And diamonds never naturally grow into the\Nshapes found in jewelry—
Dialogue: 0,0:03:31.26,0:03:36.47,Default,,0000,0000,0000,,those diamonds have been cut to \Nshowcase sparkle and clarity.
Dialogue: 0,0:03:36.47,0:03:41.62,Default,,0000,0000,0000,,Environmental conditions can also \Ninfluence whether crystals form at all.
Dialogue: 0,0:03:41.62,0:03:44.13,Default,,0000,0000,0000,,Glass is made of melted quartz sand,
Dialogue: 0,0:03:44.13,0:03:45.69,Default,,0000,0000,0000,,but it isn’t crystalline.
Dialogue: 0,0:03:45.69,0:03:48.71,Default,,0000,0000,0000,,That’s because glass cools \Nrelatively quickly,
Dialogue: 0,0:03:48.71,0:03:51.65,Default,,0000,0000,0000,,and the atoms do not have time to arrange\Nthemselves
Dialogue: 0,0:03:51.65,0:03:54.58,Default,,0000,0000,0000,,into the ordered structure \Nof a quartz crystal.
Dialogue: 0,0:03:54.58,0:03:58.35,Default,,0000,0000,0000,,Instead, the random arrangement \Nof the atoms in the melted glass
Dialogue: 0,0:03:58.35,0:04:00.91,Default,,0000,0000,0000,,is locked in upon cooling.
Dialogue: 0,0:04:00.91,0:04:03.55,Default,,0000,0000,0000,,Many crystals don’t form geometric shapes
Dialogue: 0,0:04:03.55,0:04:08.15,Default,,0000,0000,0000,,because they grow in extremely close \Nquarters with other crystals.
Dialogue: 0,0:04:08.15,0:04:10.81,Default,,0000,0000,0000,,Rocks like granite are full of crystals,
Dialogue: 0,0:04:10.81,0:04:13.38,Default,,0000,0000,0000,,but none have recognizable shapes.
Dialogue: 0,0:04:13.38,0:04:15.54,Default,,0000,0000,0000,,As magma cools and solidifies,
Dialogue: 0,0:04:15.54,0:04:21.25,Default,,0000,0000,0000,,many minerals within it crystallize at the\Nsame time and quickly run out of space.
Dialogue: 0,0:04:21.25,0:04:23.88,Default,,0000,0000,0000,,And certain crystals, like turquoise,
Dialogue: 0,0:04:23.88,0:04:28.89,Default,,0000,0000,0000,,don’t grow into any discernible geometric\Nshape in most environmental conditions,
Dialogue: 0,0:04:28.89,0:04:31.01,Default,,0000,0000,0000,,even given adequate space.
Dialogue: 0,0:04:31.01,0:04:34.20,Default,,0000,0000,0000,,Every crystal’s atomic structure has \Nunique properties,
Dialogue: 0,0:04:34.20,0:04:39.13,Default,,0000,0000,0000,,and while these properties may not have\Nany bearing on human emotional needs,
Dialogue: 0,0:04:39.13,0:04:44.20,Default,,0000,0000,0000,,they do have powerful applications \Nin materials science and medicine.